MODULE-I
What is TOC??
In theoretical computer science, the theory of computation is the branch that deals with
whether and how efficiently problems can be solved on a model of computation, using an
algorithm. The field is divided into three major branches: automata theory, computability theory
and computational complexity theory.
In order to perform a rigorous study of computation, computer scientists work with a
mathematical abstraction of computers called a model of computation. There are several models
in use, but the most commonly examined is the Turing machine.
Automata theory
In theoretical computer science, automata theory is the study of abstract machines (or more
appropriately, abstract 'mathematical' machines or systems) and the computational problems that
can be solved using these machines. These abstract machines are called automata.
This automaton consists of
• states (represented in the figure by circles),
• and transitions (represented by arrows).
As the automaton sees a symbol of input, it makes a transition (or jump) to another state,
according to its transition function (which takes the current state and the recent symbol as its
inputs).
Uses of Automata: compiler design and parsing.
Introduction to formal proof:
Basic Symbols used :
U – Union
∩- Conjunction
ϵ - Empty String
Φ – NULL set
7- negation
‘ – compliment
= > implies